This is my rig,


I use the 2 GCP for 20 available presets without going to another bank.
She consists of 9 heads, 3 amp selectors, 4 GCX units. Various effects and stuff.
GCX units 1-2 control any effect in front of amps, as well as all the heads. GCX 3 is all effect loops, and GCX 4 is all channel switching.
I can combine any combination of amp, or effect. It is actually sort of simple in its design, 4 clean heads, 4 heads with some bite, 4 80s metal type, and then 4 for very saturated. Fairly quiet, no phase issues and no hum.
Next on the list I am going to free up GCX#4 by installing 2 control switchers (thanks to John Clark for all the info) Thanks to the Voodoo lab guys for all the time answering questions
Lee